High frequency signal transmission line having ground line blocks to reduce noise
A high frequency signal transmission line having reduced noise. Particularly, a signal transmission line of the current invention has reduced radiation noise and reflection noise, because a conventional ground guard fence line disposed between signal lines is separated into a plurality of ground line blocks that are spaced apart from each other to shield against noise.
1. A printed circuit board for high frequency signal transmission, comprising:
a plurality of transmission lines patterned on a printed circuit board to transmit a high frequency signal;
a plurality of ground line blocks disposed between the transmission lines and separated from each other with a predetermined interval in a signal transmission direction to reduce noise, wherein each ground line block has a via hole; and
ground electrodes connected to the ground line block by the via hole.
2. The printed circuit board as set forth in claim 1 , wherein the ground electrodes are formed on different layers than the plurality of transmission lines and the plurality of ground line blocks.
3. The printed circuit board as set forth in claim 1 , wherein an insulating layer is disposed among the ground electrodes, the transmission lines, and the ground line blocks.
4. The printed circuit board as set forth in claim 1 , wherein the ground line blocks are spaced apart from each other by an interval (S SGFL ) represented by
S SGFL =c/ 37 ·F max
wherein c is 2.998×10 11 mm/sec that is the speed of light; F max is an operation frequency of a transmitted signal; and 37 is a relative dielectric constant of the insulating layer.
5. The printed circuit board as set forth in claim 4 , wherein F max is five times the operation frequency of the transmitted signal when the transmitted signal is a digital signal.
6. The printed circuit board as set forth in claim 4 , wherein F max is the operation frequency of the transmitted signal when the transmitted signal is a RF signal.